Checks your iTunes folder for any .ipas that look like Xamarin apps

GetXamarinApps.cs

void Main()
{
	var myXamarinApps =
		Directory
			.EnumerateFiles(Path.Combine(Environment.GetEnvironmentVariable("HOMEPATH"), @"Music\iTunes\iTunes Media\Mobile Applications"), "*.ipa")
			.Where(f=> ZipFile.Open(f, ZipArchiveMode.Read)
						.GetRawEntries()
						.Any(e=> e.FullName.Contains(".monotouch-")));
						
	foreach (var app in myXamarinApps)
		Console.WriteLine(Path.GetFileNameWithoutExtension(app));
}

// we need this because some apps contain non-windows-friendly filenames, and ZipArchive.Entries will throw 
// http://www.codeproject.com/Tips/1007398/Avoid-Illegal-Characters-in-Path-error-in-ZipArchi
public static class ZipArchiveHelper
{
  private static FieldInfo _Entries;
  private static MethodInfo _EnsureDirRead;
  static ZipArchiveHelper()
  {
    _Entries= typeof(ZipArchive).GetField("_entries",BindingFlags.NonPublic|BindingFlags.Instance);
    _EnsureDirRead = typeof(ZipArchive).GetMethod("EnsureCentralDirectoryRead", BindingFlags.NonPublic | BindingFlags.Instance);
  }
  public static List<ZipArchiveEntry> GetRawEntries(this ZipArchive archive)
  {
  	 try { _EnsureDirRead.Invoke(archive, null); } catch { }
     return (List<ZipArchiveEntry>)_Entries.GetValue(archive);
   }
}